Cigarette smoking is a major health problem in the United States. Despite wide public education efforts, a large proportion of our population continue to smoke. Research in behavioral pharmacology has indicated that drug reinforced behaviors increase during food deprivation. Specifically, animals that have been trained to self-administer drugs will show increased rates in self administration, that return to baseline levels following cessation of the deprivation condition. The present proposal will utilize this paradigm to determine the extent with which nicotine regulation in humans is increased under states of food deprivation. The analysis of the relationship between food deprivation and smoking is important in order to better understand variables that may influence smoking behavior. This is particularly relevant since many people are attempting to change their smoking and/or eating behaviors. Changes in the reinforcing value of smoking based on food deprivation is particularly relevant to understanding how dieting may influence smoking status. Three studies are planned. Nicotine self-administration will be assessed with female smokers over a four hour period following 11 hours abstinence from smoking and caloric intake. At the beginning of the observation period, subjects will be given a caloric preload beverage that with either be similar in caloric value to their normal breakfast (500 kcal) or much lower (70 kcal). Smoking will be assessed using a smoke delivery apparatus that will provide measured doses of smoke. The first study is designed to demonstrate that caloric deprivation results in increased smoking behavior. Study 2 investigates the effect of drug dose on the food deprivation/drug self-administration relationship and Study 3 investigates the effect of manipulating the taste of the caloric preload using sweet or bitter beverages.